6A40.33 Matching Index of Refraction with a Light Pipe
Refractive index, refraction
A U-rod in air transmits a laser beam like an optical fibre. When part of the rod is submerged in an index-matched mineral oil, the laser beam is no longer transmitted to the other end.
-  U-rod
-  Laser pointer
-  Glass container
-  Bottle of mineral oil
-  Roll of paper towels
- Pour the mineral oil to the glass container.
- Without submerging the U-rod in mineral oil, direct the laser beam to one end of the rod.
- Notice the glow on the other end of the rod.
- Lower the rod into the container until it is submerged in mineral oil.
- Notice the intensity of the glow decreases as the rod is lowered.
- PIRA 6A40.33
- Don't attempt this at home!
If you have any questions about the demos or notes you would like to add to this page, contact Ricky Chu at ricky_chu AT sfu DOT ca.